Grating

ABSTRACT

The invention relates to a grating consisting of parallel bearing bars connected by cross bars running perpendicular to the bearing bars, and of a frame, sheet-metal strips being located between the bearing bars. 
     In order to improve a grating of this kind in such manner that it is easier to manufacture, it is suggested within the scope of the invention that a wire be inserted under each of the cross bars and the sheet-metal strip clamped between the wires and the cross bars.

The invention relates to a grating consisting of parallel bearing bars connected by cross bars running perpendicular to the bearing bars, and of a frame, sheet-metal strips being located between the bearing bars.

Gratings of this kind are known from the applicant's product portfolio under the name “Press welded grating with perforated sheet” and are listed on page 42 of Gebr. Meiser GmbH's catalogue. These gratings are press-welded gratings made of hot-dip-galvanized steel and have a mesh spacing of 34.3×38.1 mm. The cross bars are twisted square profiles with an edge length of 5 mm, and are welded to the bearing bars. The sheet metal is configured as perforated strips with two rows of square holes. Down the middle, the strips have a profiled fin for welding to the cross bars. The frame of this grating is flat and is prior art. These gratings provide walkable surfaces and are used, for example, to cover working platforms.

Such gratings are problematic in that the twisted cross bars may protrude above the upper edge of the grating and that it is necessary not only to weld the cross bars to the bearing bars but also the perforated sheet to the cross bars; this is time-consuming and costly.

From the EP 1 205 609 A1 a grating is known that consists of parallel bearing bars connected by cross bars running perpendicular to the bearing bars, and of a frame, sheet-metal strips being located between the bearing bars. At the points where they intersect the cross bars, and between consecutive bearing bars, the sheet-metal strips have concave indentations that house the cross bars.

The object of this invention is thus to improve a grating according to the preamble in such manner that it is easier to manufacture.

This object is established according to the invention for a grating consisting of parallel bearing bars connected by cross bars running perpendicular to the bearing bars, and of a frame, sheet-metal strips being located between the bearing bars, in that a wire is inserted under each of the cross bars and the sheet-metal strip is clamped between the wires and the cross bars.

By clamping the sheet-metal strips between the wires and the cross bars, the manufacturer obviates the need to weld the strips to the cross bars, thus benefiting the production process.

A useful embodiment of the invention consists in that the cross bars are made of flat material.

This yields a planar surface, as no twisted cross bars protrude above the upper edge of the grating. Plus, the appearance of the grating is more pleasant than in the case of twisted cross bars.

In this connection, it is to advantage that the cross bars and the bearing bars are press locked.

This makes it unnecessary to weld the cross bars to the bearing bars, which means that the grating can—except for the frame—be manufactured as a press locked grating without welds. The pressing process also secures the wire within the recesses.

It is also within the scope of the invention to configure the frame as T-shaped section.

A preferred embodiment of the invention consists in that the sheet-metal strips have perforations.

In this connection, a preferred embodiment of the invention consists in that each sheet-metal strip has two rows of square perforations.

An embodiment of the invention is described below by reference to the drawings.

FIG. 1 shows a top view of a grating according to the invention;

FIG. 2 shows the grating illustrated in FIG. 1, cut along the line A-A;

FIG. 3 shows the grating illustrated in FIG. 1, cut along the line B-B.

As is evident from the drawings, the grating according to the invention consists of parallel bearing bars 1 connected by cross bars 2 running perpendicular to the bearing bars 1, and of a frame 3. Sheet-metal strips 4, each of which has two rows of square perforations 5, are fitted between the bearing bars 1.

To secure the sheet-metal strips 4, a wire 6 is inserted under each of the cross bars 2; the wire 6 runs through recesses in the bearing bars 1, and the sheet-metal strip 4 is clamped between the wires 6 and the cross bars 2.

The cross bars 2 of the grating according to the invention consist of flat material and are joined to the bearing bars 1 by application of pressure. This pressing process thus serves to join the bearing bars 1 and the cross bars 2 with each other, and to secure the wire 6 in the recesses; the sheet-metal strips 4, for their part, are secured between the wire 6 and the cross bars 2. The welding steps that would otherwise be required are thus rendered unnecessary.

A welding step is needed only to secure the frame 3, which is preferably configured as T-shaped section.

Gratings according to the invention can be manufactured directly in the desired width, whereas prior art gratings of narrow widths first had to be cut out of a 1-m-wide grating, making production more complicated. 

1. A grating consisting of parallel bearing bars connected by cross bars running perpendicular to the bearing bars, and of a frame, sheet-metal strips being located between the bearing bars, wherein a wire (6) is inserted under each of the cross bars (2) and the sheet-metal strip (4) is clamped between the wires (6) and the cross bars (2).
 2. The grating of claim 1, wherein the cross bars (2) consist of flat material.
 3. The grating of claim 2, wherein the cross bars (2) and the bearing bars (1) are press locked.
 4. The grating of claim 1, wherein the frame (3) is of T-shape configuration.
 5. The grating of claim 1, wherein the sheet-metal strips (4) have perforations (5).
 6. The grating of claim 5, wherein each sheet-metal strip (4) has two rows of square perforations (5). 